Merge pull request #5899 from dgquintas/uchannels_kthxbai

removed uchannels

3 files changed, 2 insertions, 296 deletions

diff --git a/src/core/channel/client_uchannel.c b/src/core/channel/client_uchannel.c
deleted file mode 100644
index d32327206e..0000000000
--- a/src/core/channel/client_uchannel.c
+++ /dev/null
@@ -1,233 +0,0 @@
-/*
- *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#include "src/core/channel/client_uchannel.h"
-
-#include <string.h>
-
-#include "src/core/census/grpc_filter.h"
-#include "src/core/channel/channel_args.h"
-#include "src/core/channel/client_channel.h"
-#include "src/core/channel/compress_filter.h"
-#include "src/core/channel/subchannel_call_holder.h"
-#include "src/core/iomgr/iomgr.h"
-#include "src/core/support/string.h"
-#include "src/core/surface/channel.h"
-#include "src/core/transport/connectivity_state.h"
-
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-#include <grpc/support/sync.h>
-#include <grpc/support/useful.h>
-
-/** Microchannel (uchannel) implementation: a lightweight channel without any
- * load-balancing mechanisms meant for communication from within the core. */
-
-typedef struct client_uchannel_channel_data {
-  /** master channel - the grpc_channel instance that ultimately owns
-      this channel_data via its channel stack.
-      We occasionally use this to bump the refcount on the master channel
-      to keep ourselves alive through an asynchronous operation. */
-  grpc_channel_stack *owning_stack;
-
-  /** connectivity state being tracked */
-  grpc_connectivity_state_tracker state_tracker;
-
-  /** the subchannel wrapped by the microchannel */
-  grpc_connected_subchannel *connected_subchannel;
-
-  /** the callback used to stay subscribed to subchannel connectivity
-   * notifications */
-  grpc_closure connectivity_cb;
-
-  /** the current connectivity state of the wrapped subchannel */
-  grpc_connectivity_state subchannel_connectivity;
-
-  gpr_mu mu_state;
-} channel_data;
-
-typedef grpc_subchannel_call_holder call_data;
-
-static void monitor_subchannel(grpc_exec_ctx *exec_ctx, void *arg,
-                               bool iomgr_success) {
-  channel_data *chand = arg;
-  grpc_connectivity_state_set(exec_ctx, &chand->state_tracker,
-                              chand->subchannel_connectivity,
-                              "uchannel_monitor_subchannel");
-  grpc_connected_subchannel_notify_on_state_change(
-      exec_ctx, chand->connected_subchannel, NULL,
-      &chand->subchannel_connectivity, &chand->connectivity_cb);
-}
-
-static char *cuc_get_peer(grpc_exec_ctx *exec_ctx, grpc_call_element *elem) {
-  return grpc_subchannel_call_holder_get_peer(exec_ctx, elem->call_data);
-}
-
-static void cuc_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
-                                          grpc_call_element *elem,
-                                          grpc_transport_stream_op *op) {
-  GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
-  grpc_subchannel_call_holder_perform_op(exec_ctx, elem->call_data, op);
-}
-
-static void cuc_start_transport_op(grpc_exec_ctx *exec_ctx,
-                                   grpc_channel_element *elem,
-                                   grpc_transport_op *op) {
-  channel_data *chand = elem->channel_data;
-
-  grpc_exec_ctx_enqueue(exec_ctx, op->on_consumed, true, NULL);
-
-  GPR_ASSERT(op->set_accept_stream == false);
-  GPR_ASSERT(op->bind_pollset == NULL);
-
-  if (op->on_connectivity_state_change != NULL) {
-    grpc_connectivity_state_notify_on_state_change(
-        exec_ctx, &chand->state_tracker, op->connectivity_state,
-        op->on_connectivity_state_change);
-    op->on_connectivity_state_change = NULL;
-    op->connectivity_state = NULL;
-  }
-
-  if (op->disconnect) {
-    grpc_connectivity_state_set(exec_ctx, &chand->state_tracker,
-                                GRPC_CHANNEL_FATAL_FAILURE, "disconnect");
-  }
-}
-
-static int cuc_pick_subchannel(grpc_exec_ctx *exec_ctx, void *arg,
-                               grpc_metadata_batch *initial_metadata,
-                               grpc_connected_subchannel **connected_subchannel,
-                               grpc_closure *on_ready) {
-  channel_data *chand = arg;
-  GPR_ASSERT(initial_metadata != NULL);
-  *connected_subchannel = chand->connected_subchannel;
-  return 1;
-}
-
-/* Constructor for call_data */
-static void cuc_init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                               grpc_call_element_args *args) {
-  grpc_subchannel_call_holder_init(elem->call_data, cuc_pick_subchannel,
-                                   elem->channel_data, args->call_stack);
-}
-
-/* Destructor for call_data */
-static void cuc_destroy_call_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_call_element *elem) {
-  grpc_subchannel_call_holder_destroy(exec_ctx, elem->call_data);
-}
-
-/* Constructor for channel_data */
-static void cuc_init_channel_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_channel_element *elem,
-                                  grpc_channel_element_args *args) {
-  channel_data *chand = elem->channel_data;
-  memset(chand, 0, sizeof(*chand));
-  grpc_closure_init(&chand->connectivity_cb, monitor_subchannel, chand);
-  GPR_ASSERT(args->is_last);
-  GPR_ASSERT(elem->filter == &grpc_client_uchannel_filter);
-  chand->owning_stack = args->channel_stack;
-  grpc_connectivity_state_init(&chand->state_tracker, GRPC_CHANNEL_IDLE,
-                               "client_uchannel");
-  gpr_mu_init(&chand->mu_state);
-}
-
-/* Destructor for channel_data */
-static void cuc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
-                                     grpc_channel_element *elem) {
-  channel_data *chand = elem->channel_data;
-  /* cancel subscription */
-  grpc_connected_subchannel_notify_on_state_change(
-      exec_ctx, chand->connected_subchannel, NULL, NULL,
-      &chand->connectivity_cb);
-  grpc_connectivity_state_destroy(exec_ctx, &chand->state_tracker);
-  gpr_mu_destroy(&chand->mu_state);
-  GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, chand->connected_subchannel,
-                                  "uchannel");
-}
-
-static void cuc_set_pollset(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                            grpc_pollset *pollset) {
-  call_data *calld = elem->call_data;
-  calld->pollset = pollset;
-}
-
-const grpc_channel_filter grpc_client_uchannel_filter = {
-    cuc_start_transport_stream_op, cuc_start_transport_op, sizeof(call_data),
-    cuc_init_call_elem, cuc_set_pollset, cuc_destroy_call_elem,
-    sizeof(channel_data), cuc_init_channel_elem, cuc_destroy_channel_elem,
-    cuc_get_peer, "client-uchannel",
-};
-
-grpc_connectivity_state grpc_client_uchannel_check_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, int try_to_connect) {
-  channel_data *chand = elem->channel_data;
-  grpc_connectivity_state out;
-  gpr_mu_lock(&chand->mu_state);
-  out = grpc_connectivity_state_check(&chand->state_tracker);
-  gpr_mu_unlock(&chand->mu_state);
-  return out;
-}
-
-void grpc_client_uchannel_watch_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, grpc_pollset *pollset,
-    grpc_connectivity_state *state, grpc_closure *on_complete) {
-  channel_data *chand = elem->channel_data;
-  gpr_mu_lock(&chand->mu_state);
-  grpc_connectivity_state_notify_on_state_change(
-      exec_ctx, &chand->state_tracker, state, on_complete);
-  gpr_mu_unlock(&chand->mu_state);
-}
-
-grpc_channel *grpc_client_uchannel_create(grpc_subchannel *subchannel,
-                                          grpc_channel_args *args) {
-  grpc_channel *channel = NULL;
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-
-  channel =
-      grpc_channel_create(&exec_ctx, NULL, args, GRPC_CLIENT_UCHANNEL, NULL);
-
-  return channel;
-}
-
-void grpc_client_uchannel_set_connected_subchannel(
-    grpc_channel *uchannel, grpc_connected_subchannel *connected_subchannel) {
-  grpc_channel_element *elem =
-      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(uchannel));
-  channel_data *chand = elem->channel_data;
-  GPR_ASSERT(elem->filter == &grpc_client_uchannel_filter);
-  gpr_mu_lock(&chand->mu_state);
-  chand->connected_subchannel = connected_subchannel;
-  GRPC_CONNECTED_SUBCHANNEL_REF(connected_subchannel, "uchannel");
-  gpr_mu_unlock(&chand->mu_state);
-}
diff --git a/src/core/channel/client_uchannel.h b/src/core/channel/client_uchannel.h
deleted file mode 100644
index 8bb288e7d4..0000000000
--- a/src/core/channel/client_uchannel.h
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#ifndef GRPC_CORE_CHANNEL_CLIENT_UCHANNEL_H
-#define GRPC_CORE_CHANNEL_CLIENT_UCHANNEL_H
-
-#include "src/core/channel/channel_stack.h"
-#include "src/core/client_config/resolver.h"
-
-#define GRPC_MICROCHANNEL_SUBCHANNEL_ARG "grpc.microchannel_subchannel_key"
-
-/* A client microchannel (aka uchannel) is a channel wrapping a subchannel, for
- * the purposes of lightweight RPC communications from within the core.*/
-
-extern const grpc_channel_filter grpc_client_uchannel_filter;
-
-grpc_connectivity_state grpc_client_uchannel_check_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, int try_to_connect);
-
-void grpc_client_uchannel_watch_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, grpc_pollset *pollset,
-    grpc_connectivity_state *state, grpc_closure *on_complete);
-
-grpc_channel *grpc_client_uchannel_create(grpc_subchannel *subchannel,
-                                          grpc_channel_args *args);
-
-void grpc_client_uchannel_set_connected_subchannel(
-    grpc_channel *uchannel, grpc_connected_subchannel *connected_subchannel);
-
-#endif /* GRPC_CORE_CHANNEL_CLIENT_UCHANNEL_H */
diff --git a/src/core/channel/subchannel_call_holder.h b/src/core/channel/subchannel_call_holder.h
index 9086cdc882..84b4657db4 100644
--- a/src/core/channel/subchannel_call_holder.h
+++ b/src/core/channel/subchannel_call_holder.h
@@ -55,15 +55,14 @@ typedef enum {
     for initial metadata before trying to create a call object,
     and handling cancellation gracefully.
 
-    Both the channel and uchannel filter use this as their call_data. */
+    The channel filter uses this as their call_data. */
 typedef struct grpc_subchannel_call_holder {
   /** either 0 for no call, 1 for cancelled, or a pointer to a
       grpc_subchannel_call */
   gpr_atm subchannel_call;
   /** Helper function to choose the subchannel on which to create
       the call object. Channel filter delegates to the load
-      balancing policy (once it's ready); uchannel returns
-      immediately */
+      balancing policy (once it's ready). */
   grpc_subchannel_call_holder_pick_subchannel pick_subchannel;
   void *pick_subchannel_arg;